Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
ban hanh » ban hang
nam thuc » nam thuoc, am thuc, nam thu
va dinh » van dinh, va kinh, va tinh
nang ma » tang ma, sang ma, nang cao
hieu le » hieu ve, hieu he, hieu ly
su sac » su sach, su cac, su xac
sac ky » cac ky, sai ky
le nam » ly nam, he nam, le na

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sac ky ((mang may) or (nang ma)) hoi. hieu le nam thuc ((ban hanh) or (va dinh)) dai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sac ky ((mang may) OR (nang ma)) hoi. hieu le nam thuc ((ban hanh) OR (va dinh)) dai cua viet.
• Adding a wildcard symbol may retrieve word variants: su sac ky ((mang may) or (nang ma)) hoi. hieu le nam thuc ((ban hanh) or (va dinh)) dai cua viet*.